1. On the way to work on Thursday, I stopped to fill it up. It would not start, so I got a jump and went directly to Discount Auto parts. Yanked both batteries out and both were low on CCA, so with a quick charge on both batteries, they conducted a alternator check and told me that it was bad. now with the correct alternator installed, I thought that everything would be good. Well ever since thursday after the alternator changed, my battery light will not go out. I took it back to Discount Auto and they re-checked both batteries, which were good. So they hooked up the scanner and moved to the voltage side of the scanner, and found that the computer is only allowing 11.9-12.3 volts (with nothing on) 11.3-11.7 (with high beams and fan on high). The guy seems to think that's why my battery light is on. If you can help me out in any way Please post reply.

2. When the truck hits 45-50 mph it starts to shake. Please help me on this one as well. Sorry I can not get into more detail.

 

It's not the computer allowing the low voltage it's the alternator that's bad. Remove the alternator and have it tested separately.

The transmission shake I can't help you with but it's typically not the transmission.

 

I agree, your alternator is bad. My two stock ones only lasted 80,000 miles, I am on my third. Go to the tire store and re-balance your tires. Once I purchase new tires and had to go back for a shake, the shop told me that have a balance machine that needed to be re-calibrated.

 

But if it was the tires wouldn't it happen at all speeds and not just between 45-50?

 

No, tire imbalance usually has that characteristic of only vibrating at certain speeds.

Kind of like my wife...

Josh

 

Tim's 100% correct. The voltage regulator on a single alt. truck is in the alternator, not the computer. That guy at Discount should stick to the cash register.

 

I have 200,000 now and I have been through many brands or tires and situations. My favorite are 285/65 BF All Terrain KO's. When my hubs went bad, I had no vibration, but from time to time, I get a harmonic that clears up after I get the tires balanced. Once I tried the no weight 6oz, beads you add inside the tire, (cant remember the brand) this was good for me for the life of these tires.

 

order a DC POwer alternator you will be glad you did

Theres alot of expensive electronics at risk when there is a charging system problem